National Weather Service Forecast for: Mount Prospect IL
Issued by: National Weather Service Chicago, IL
Updated: 9:56 pm CDT Jun 29, 2026
 
Tonight

Tonight: Mostly clear, with a low around 79. South southwest wind around 10 mph, with gusts as high as 20 mph.
Mostly Clear

 Tuesday

Tuesday: Sunny and hot, with a high near 96. Heat index values as high as 107. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Hot

 Tuesday
Night
Tuesday Night: Mostly clear, with a low around 78. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Mostly Clear

 Wednesday

Wednesday: Sunny and hot, with a high near 97. Heat index values as high as 103. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Hot

 Wednesday
Night
Wednesday Night: Mostly clear, with a low around 79. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Mostly Clear

 Thursday

Thursday: Mostly sunny and hot, with a high near 95.
Hot

 Thursday
Night
Thursday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 76. Chance of precipitation is 60%.
Chance
T-storms then
Showers
Likely
 Friday

Friday: A chance of showers and thunderstorms. Partly sunny, with a high near 91.
Chance
T-storms

 Friday
Night
Friday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 73.
Chance
T-storms
Lo 79 °F Hi 96 °F Lo 78 °F Hi 97 °F Lo 79 °F Hi 95 °F Lo 76 °F Hi 91 °F Lo 73 °F

Extreme Heat Warning
Hazardous Weather Outlook
 

Tonight
 
 Mostly clear, with a low around 79. South southwest wind around 10 mph, with gusts as high as 20 mph.
Tuesday
 
 Sunny and hot, with a high near 96. Heat index values as high as 107. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
 
 Mostly clear, with a low around 78. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
 
 Sunny and hot, with a high near 97. Heat index values as high as 103. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
 
 Mostly clear, with a low around 79. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday
 
 Mostly sunny and hot, with a high near 95.
Thursday Night
 
 A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 76. Chance of precipitation is 60%.
Friday
 
 A chance of showers and thunderstorms. Partly sunny, with a high near 91.
Friday Night
 
 A chance of showers and thunderstorms. Mostly cloudy, with a low around 73.
Independence Day
 
 A chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 87.
Saturday Night
 
 A chance of showers and thunderstorms. Partly cloudy, with a low around 71.
Sunday
 
 A chance of showers and thunderstorms. Partly sunny, with a high near 86.
Sunday Night
 
 A chance of showers and thunderstorms. Mostly cloudy, with a low around 69.
Monday
 
 Mostly sunny, with a high near 84.

 

Forecast from NOAA-NWS for Mount Prospect IL.